Pulley-block



v 2 Sheets-Sheet 1. J. W. NORGROSS.

PULLEY BLOCK.

Patented Aug. 30,1881.

'III-III INVENTOR (No Model.)

WITNESSESI M/M 2 Sheets-Sheet@ (No Model.)

J. W.' NORCROSS.

PULLEY BLOCK.

Patented Aug. 30,1881.

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a ql` WITNESSES: INVENTOR:

' my/ MMn/mos n d d @man f We @Mg/72k UNTTTSD STATES PATENT OFFICE.

JOSEPH w. Noacaoss, OF BOSTON, MASSACHUSETTS.

PU LLEY-BLOCK.

SPECIFICATION forming part of Letters Patent No. 246,541, dated August 30, 1881.

Application filed February 15, 1881.

To all whom 'it may concern Be it known that I, JOSEPH W. NORGROSS, of thecity Ot' Boston, county ot' Suffolk, and State of Massachusetts, have invented a new and usefullmprovementin Pulley-Blocks; and I hereby declare that the following is a full, clear, and exact description of the same, reference beinghad to the accompanying drawings, forming part of this specilication.

This invention relates to that class ot' pulley-blocks in which wooden cheek-pieces are provided on their inner and outer faces with metal strips, which are connected together at their upper and lower ends by transverse pins or bolts, andat or near their middle portions form the bearings or supports for the axial pin of the sheave.

My'improvements are embodied in the pulley blocks illustrated in the accompanying drawings, in which- Figure l is a perspective view ot' a single pulley-block, one-half of the front cheek Or side being shown as cutaway. Fig. 2 is a sectional View of the same. Fig. 3 is an enlarged view, showing the axle-bearin g for the pulley. Fig. 4 is a viewotl the upper end of the block,showing the manner in which the two sides of the block are secured together. Fig. 5 is a perspective view of the distance-piece shown in Fig. 4 placed between the sides. Fig. 6 is a view, partly in section, of a double pulleyblock.

The object of this invention is to simplify the construction, increase the strength of pulley-blocks, and to facilitate the separating ot the blocks for repairing, cleaning, or oiling.

In the drawings, a c are straight straps, provided at each end with holes. These straps are placed on the inner side ofthe cheeks c c, and form, when connected, a stron g strap-link and the main support of the pulley-bearin gs.

b b are bent straps secured at the ends to the straps c c, and passing around the cheeks c c on the outside` d d are distance-pieces placed between the straps c c, and c e are bolts provided with nuts,by which the blocks are secured firmly together and the straps, the checks, or sides (No model.)

united to form a strong and durable pulleyblock, which can bereadilyseparated byremoving the nuts from the bolts e e, and as readily put together, all strain being resisted by the straight straps a. c.

ff are the pulleys, and g g the anti-friction wheels on which the axle of the pulley rests. To give to the axles ot' the wheels g g a long bearing, the bushing his secured on the straps a a by casting the bushing with two projecting pins, which, passing through holes in the straps, are riveted on the inside. The bushing h is secured in the same manner to the strap b, and thus a long bearing secured. The bushings hand hare preferably made Ofbronze or other suitable metal to resist wear and reduce friction.

The straps a and b are secured together by means of the stay i, which is riveted into the strap c and secured to the strap b by a nut. rlhe cheek or side c is thus more firmly held in place. The stay z' also forms the thrust-bearing for the axle ofthe pulley f. and in a double block is riveted to both of the straps Lain the central cheek, as is shown in Fig. 6.

The cheeks or sides c c are made of wood to form guides for the rope and prevent sha-ving or injuring the same; but all the strain is taken up by the metal straps. When any part requires repairing or Oiling, the block can be quickly taken apart and the repairs made, and as all the parts for blocks of a given number or size are made after standard gages, the various parts can be kept in stock, and single, double, or triple sheave-blocks canv be made up at any time by simply bolting the parts together.

It will be observed by referring toA Fig. 6 that each sheave or pulley has an axle independentof the axle of the other sheave. This allows the sheaves to turn independently ot' each other.

Having thus described my invention, I claim as new and desire to secure byLetters Patentl. A pulley-block combiningin its structure the inner straps, c c, the outer straps, b b, the wooden cheeks c c, interposed between said straps, the end bolts passing through all the straps and connecting them together, and a and eonneotingtheinner and outer straps, subsheave having an axial pin extending through stan tially as described. 1o the inner straps, but not through the outer In witness whereof I have hereunto aixed straps, substantially as shown and described. 1n y name.

5 2. In 2t pulley-block7 the combination ofthe JOSEPH NORCROSS.

inner straps, a a, the outer straps, b b, the fituessesz wooden oheekpieces c c, interposed between J. A. MILLER, Jr., the straps, with the sta-ys fi, passing through XVM. L. COOP. 

